One of the easiest shrubs to identify throughout the year (unless mistaken for poison sumac, in the absence of mature fruit), smooth sumac has a spreading, open-growing shrub growing up to 3 m (9.8 ft) tall, rarely to 5 m (16 ft). The leaves are alternate, 30–50 cm (12–20 in) long, compound with 11–31 oppositely pairedleaflets, each leaflet 5–11 cm (2–41⁄4 in) long, with a serrated margin. The leaves turn scarlet in the fall. The flowers are tiny, green, produced in dense erect panicles 10–25 cm (4–10 in) tall, in the spring, later followed by large panicles of edible crimson berries that remain throughout the winter. The buds are small, covered with brown hair and borne on fat, hairless twigs. The bark on older wood is smooth and grey to brown.

Fruit

In late summer it sometimes forms galls on the underside of leaves, caused by the parasitic sumac leaf gall aphid, Melaphis rhois. The galls are not harmful to the tree.